1957 - 1962 . 
Tabb, D. C., D. L. Dubrow and A. C. Jones (1962) Studies on the biology of the pink shrimp, 
Penaeus duorarum Burkenroad, in Everglades National Park, Florida. Fla. St. Bd. Conserv. 
Tech. Ser. No. 37. Florida State Board of Conservation, Tallahassee, FL. 32 pp. 
The biology of pink shrimp of northern Florida Bay was studied in conjunction with 
other studies on the ecology of estuarine plants and animals in a natural fluctuating 
environment. More than 25,000 juvenile pink shrimp collected during the period 
September, 1957, through April 1962 were examined for length and sex composition. 
Pink shrimp enter the Coot Bay area as postlarvae with a minimum carapace length of 
1.7 mm and with 4 dorsal spines on the rostrum. The modal carapace length of entering 
postlarvae was 1.8 mm. with six dorsal and no ventral rostral spines. There appear to 
be peaks of postlarval abundance in the spring and early summer, low numbers in the 
late summer and fall and increasing numbers again beginning about November. 
Postlarvae enter the Coot Bay area on the flooding tides at night traversing the 3 mi 
length of Buttonwood Canal in approximately one hour at the peak velocity of the tide. 
Peak numbers of postlarvae in samples usually occur at the peak velocity of the 
flooding tides. Night plankton samples usually produce more postlarvae than day time 
samples. Catch-per-unit-effort data indicate that juvenile pink shrimp are most 
abundant during the period June through September. A smaller peak abundance is 
usually found sometime during the period February through May. Lowest catch rates 
normally occur in December and January. Among large samples of juvenile pink shrimp 
the sex ratio consisted of about 50% females and 50% males, however, small samples 
may show wide departure from a 1:1 ratio. Predation by fish is probably the major 
cause of shrimp mortality in southern Florida estuarine areas. Shrimp infected with 
sporozoan parasites causing the condition known as 'cotton shrimp' were detected in 
only two instances during 55 months of sampling. Pink shrimp are sensitive to sudden 
cold temperatures of winter and respond by moving to deeper water. With warming of 
the shallows they move back unless they have reached the size for final emigration. 
Mass mortality of pink shrimp was observed following hurricane Donna. Deaths were 
caused by storm turbulence, stranding and post-hurricane oxygen depletion. Carapace 
length-frequency distributions show time and characteristics of periods of juvenile 
immigration into the nursery, and size at time of emigration to the offshore grounds. 
Orderly progression of modal groups along a similar pattern each year, followed by a 
sharp regression of size in June-July can be interpreted as indications of growth 
patterns and completion of offshore movement respectively. An average monthly 
carapace length increase of about 2 mm and a maximum of 3 to 4 mm is suggested by 
length frequency studies. Few shrimp having carapace lengths greater than 25 mm 
were taken in Coot Bay samples. This suggests that most have moved out of Coot Bay 
prior to attainment of that size. Petersen tags were used in an attempt to learn 
whether the shrimp of the mainland nursery areas actually did contribute to the 
Tortugas fishery. One shrimp, tagged in Coot Bay and recovered 123 days later in the 
Tortugas fishery, had increased from 110 count to 36 count per pound (heads off), and 
in carapace length from 21 to 32 mm. Three kinds of shrimp movement were noted; 
daily movement within the bay systems back and forth with the tides, short-term 
offshore movements to escape winter cold, and mass movement offshore in response to 
abnormal weather and water conditions attendant with hurricanes. Catches of small 
shrimp in the Tortugas during September and October, 1960, following hurricane Donna 
were far greater than the average for the same months of the preceding three years. 
The post-hurricane catches in the Tortugas contained much higher percentages of very 
small shrimp than usual at that time of year and suggests that hurricanes can cause 
shrimp to move offshore earlier and at a smaller size than is normal. Pink shrimp are 
tolerant of wide ranges in salinity. Postlarvae and juveniles to 28 mm. carapace length 
were taken throughout the full range of salinity observed in the study area. The general 
scarcity of shrimp larger than 28 mm carapace length in salinity lower than 32 °/oo 
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